When an electronic device is put into service, oftentimes the internal programs for running the device or functions performed by such device require alteration or updating. This is done in the prior art by inputting into such device a new program or new update codes. Whitley et al. U.S. Pat. No. 5,590,373 discloses one such method of updating the programs in an electronic device, in this instance a field programmable personal communications device (PDI). To achieve the updating of the programs within the PDI, Whitley teaches that a PCMCIA (Personal Computer Memory Card International Association) card could be used. In particular, a new program is stored in the PCMCIA card and, upon insertion of this card into the appropriate receptacle of the PDI device, the new program is transferred into the electrically programmable read only memory (EPROM) of the PDI so that the functions performed by the PDI may be reconfigured. In otherwords, the program within the PDI is replaced by the new program fed thereinto by the PCMCIA card. It means that the PCMCIA card has to have sufficient memory, particularly when a large program is to be stored therein, for reconfiguring the PDI. Furthermore, problems may be encountered when updating the internal program of the PDI with the new program from the PCMCIA card, insofar as oftentimes some type of interaction has to take place between the user and the device, as the new program is being loaded into the PDI device.
The prior art further teaches that a memory card such as a PCMCIA card may be used for transferring information between a standalone device, such as for example a vending machine or a parking meter, so that data may be transferred between the memory card and the device. One such example is disclosed in Cagliostro U.S. Pat. No. 5,500,517 which discloses the use of a PCMCIA card for transferring information to a device for updating the cost for using the device and the prices of goods to be sold from the device.
In terms of medical devices, Armstrong et al. U.S. Pat. No. 5,606,978 discloses a heart monitoring device that has a slot for accepting an IC card, which contains specific control data that is used to control the programs stored in the device, to thereby control the operation of the device. Moberg U.S. Pat. No. 5,265,607 also discloses a medical device, in this instance an EEG monitor that includes a head box that has a housing adapted to be fitted with a configuration card. Such configuration card is electrically and mechanically compatible with the housing and is configured to provide a particular type of monitoring procedure so that a specific type of EEG waveform from the patient may be monitored.
In a medical environment, it is desirable that a care provider not be distracted by having to deal with the reprogramming of a device, as is required in the prior art discussed above. Moreover, any function to be performed by a device in a medical setting has to be reliable, i.e., it has to be fully tested when the device is put into service. Any tuning or tampering of the program in order to make it run properly in such medical device is unacceptable in a patient environment. Accordingly, a foolproof method of providing a new function to a device, especially a medical device, is required.